1. Field of the Invention
This invention relates to an optical connector used in the field of optical communication for an OA equipment, an FA equipment, an on-vehicle equipment and so on.
2. Description of the Related Art
There is known a conventional optical connector of the type (as disclosed in JP-A-5-3330) in which in order to deal with noises, an optical element is received within a metal casing, and this casing is received with in a housing made of an insulative resin. This optical connector is of such a construction that when it is mounted on and fixed to a circuit board, the metal casing is disposed on a grounding circuit, formed on the circuit board, in order to shut off electromagnetic noises.
In order to enhance the effect of radiating heat generated from the optical element, a radiating portion is formed on the metal casing, and this radiating portion extends to the exterior of the housing.
On the other hand, in order to enhance the heat-radiating ability of the optical element, the optical element is so designed that an element body portion of the optical element can be disposed in intimate contact with an inner surface of a receiving recess in the metal casing, and an opening of the receiving recess is so sized and shaped that the element body portion of the optical element can be very closely fitted into this receiving recess.
Therefore, in order that lead terminals, projecting from the element body portion, could be connected to predetermined holes in the circuit board without contacting that portion of the metal casing, surrounding these lead terminals, the precise positioning of the optical element need to be effected at the optical element-receiving portion.
And besides, there was a possibility that a peripheral edge portion of the opening of the receiving recess in the metal casing was contacted with the circuit pattern, to which the lead terminals were connected, thus inviting short-circuiting.
This invention has been made to solve the above problems with the related art, and therefore it is an object of the invention to provide an optical connector in which without the need for strictly positioning an optical element, the short-circuiting, caused by contact of lead terminals with a connector housing/a metal casing, and the short-circuiting, caused by contact of the connector housing/the metal casing with a circuit pattern other than a grounding circuit, can be efficiently prevented.
To achieve the above object, according to one aspect of this invention, there is provided an optical connector wherein an element body portion of an optical element is fittingly received in a receiving recess formed in a connector housing, and lead terminals of the optical element project outwardly from the receiving recess; and the connector housing is made of a metal material; and a ground contact surface for being held in surface-to-surface contact with a grounding circuit is formed on and projects from a mounting side surface of the connector housing beyond which the lead terminals project outwardly; and an insulating portion, made of an insulating material, is formed at a peripheral edge portion of an opening of the receiving recess over an entire periphery thereof.
According to another aspect of the invention, there is provided an optical connector wherein an element body portion of an optical element is fittingly received in a receiving recess formed in a connector housing, and lead terminals of the optical element project outwardly from the receiving recess; and the connector housing is made of a metal material; and a ground contact surface for being held in surface-to-surface contact with a grounding circuit is formed on and projects from a mounting side surface of the connector housing beyond which the lead terminals project outwardly; and a non-contact recess is formed at a peripheral edge portion of an opening of the receiving recess over an entire periphery thereof so that when the ground contact surface is held in the surface-to-surface contact, a non-contact gap, at which the connector housing is out of contact with a mounting surface for the connector housing, is formed at the peripheral edge portion of the opening over the entire periphery thereof.
A radiating fin portion of a generally corrugated shape can be formed on an outer surface of the connector housing.
According to a further aspect of the invention, there is provided an optical connector wherein an element body portion of an optical element is fittingly received in a receiving recess formed in a metal casing, and lead terminals of the optical element project outwardly from the receiving recess, and the metal casing is received and held in a connector housing; and that side surface of the metal casing, beyond which the lead terminals project outwardly, serves as a ground contact surface for being held in surface-to-surface contact with a grounding circuit; and an insulating portion, made of an insulating material, is formed at a peripheral edge portion of an opening of the receiving recess over an entire periphery thereof.
According to a further aspect of the invention, there is provided an optical connector wherein an element body portion of an optical element is fittingly received in a receiving recess formed in a metal casing, and lead terminals of the optical element project outwardly from the receiving recess, and the metal casing is received and held in a connector housing; and that side surface of the metal casing, beyond which the lead terminals project outwardly, serves as a ground contact surface for being held in surface-to-surface contact with a grounding circuit; and a non-contact recess is formed at a peripheral edge portion of an opening of the receiving recess over an entire periphery thereof so that when the ground contact surface is held in the surface-to-surface contact, a non-contact gap is formed at the peripheral edge portion of the opening over the entire periphery thereof.
In one preferred construction, the metal casing is received and held in the connector housing in such a manner that one side surface of the metal casing is exposed to the exterior, and a radiating fin portion of a generally corrugated shape is formed on the exposed surface of the metal casing.